refactor: Move Astro to root, use PORT env (default 80), allow all hosts

- Move Astro files from dealplustech-astro/ to project root
- Update Dockerfile: PORT environment variable (default 80)
- Add vite.config.ts with allowedHosts: true
- Matches nixpacks behavior for Easypanel deployment
- No hardcoded ports or domains

node_modules/stringify-entities/lib/util/to-hexadecimal.js

@@ -0,0 +1,16 @@
+const hexadecimalRegex = /[\dA-Fa-f]/
+
+/**
+ * Configurable ways to encode characters as hexadecimal references.
+ *
+ * @param {number} code
+ * @param {number} next
+ * @param {boolean|undefined} omit
+ * @returns {string}
+ */
+export function toHexadecimal(code, next, omit) {
+  const value = '&#x' + code.toString(16).toUpperCase()
+  return omit && next && !hexadecimalRegex.test(String.fromCharCode(next))
+    ? value
+    : value + ';'
+}